While boats have been known and built since time immemorial and trains have become an efficient means of transportation since the industrial revolution, heretofore the limits of technology have made it impossible to combine the two means of transportation in a successful manner. There have been, recently, innovations in water-craft, such as hydrofoils and hovercrafts, but these are limited in size, as are conventional ships, because of various factors. The "hydrotrain" of the present invention is, however, related to the above-mentioned water-craft, being composed of a plurality of coaches joined together and adapted to travel specifically over water (without necessarily excluding other surfaces).
Conventional trains have coaches or freight cars coupled together by a means which allows for lateral pivoting or yaw of one car relative to another joined to it, thereby enabling the train to travel in a curve without derailing.
If such a train were to be adapted to travel over water, such as a river, lake, lagoon or the sea, an ordinary coupling means would be inadequate because of agitation and waves on the water surface. For instance, a wave encountering one of the coaches would lift the latter relative to the forward and rear coaches coupled to it, causing a great strain on a conventional coupling means. On the other hand, an articulated coupling means designed for pitch movement (longitudinal pivoting in the vertical plane), as well as lateral movement, would ensure a comfortable and safe transportation, whether for cargo or passengers.
Although such an articulated coupling means would have to be very strong, especially for a "hydrotrain" navigating a trans-ocean route, the state of the mechanical art makes such a means possible.